Apparatus for the control of railway-switches



C. W. DUNHAM. APPARATUS FOR THE CONTROL OF RAILWAY SWITCHES.

APPLICAT ON FILED JULY 911920.

C. W. DUNHAM.

APPARATUS FOR THE CONTROL OF RAILWAY SWITCHES.

APPLICATION FILED .IULY 9|1920.

mm m 8 m N T J E w n w I. M 2 QNb Y n B m .HKS P W M ATTORNEY UNITEDSTATES PATENT OFFICE.

CHARLES W. DUNHAM, OF FAIRMONT, PENNSYLVANIA, ASSIGNOR TO THE UNIONSWITCH & SIGNAL COMPANY, OF SWISSVALE, PENNSYLVANIA, A CORPORATION OFPENNSYLVANIA.

APPARATUS FOR THE CONTROL OF RAILWAY-SWITCHES.

Specification of Letters Patent.

Patented Nov. 8, 1921.

Application filed July 9, 1920. Serial No. 395,055.

To aZZ whom it may concern:

Be it known that I, CHARLES TV. DUNHAM, a citizen of the United States,residing at Fairmont, in the county of \Vestmoreland and State ofPennsylvania, have invented certain new and useful Improvements inApparatus for the Control of Railway- Switches, of which the followingis a specification.

My invention relates to apparatus for controlling railway switches, andparticularly to apparatus of the type comprising a fluid pressure motorfor actuating the switch, a manually operable lever for governing themotor, and indication means associated with the switch for locking andreleasing the lever.

One object of my invention is the provision, in connection withapparatus of this character, of mechanism for preventing the indicationmeans from releasing the lever unless the pressure of the fluid in themotor has decreased to at least a given value.

I will describe two forms of apparatus embodying my invention, and willthen point out the novel features thereof in claims.

In the accompanying drawings, Figure l is a view, partly diagrammatic,showing one form of apparatus embodying my invention, and Fig. 2 is afragmentary view showing a modification of a portion of the apparatusshown in Fig. 1 and also embodying my invention.

Similar reference characters refer to similar parts in the two views.

Referring first to Fig. 1, the reference character A designates arailway switch which is operated by a fluid pressure motor B, and whichmotor is controlled by a manually operable lever L. This lever isusually one of a plurality of similar levers in an interlocking machine.

The motor B comprises a cylinder 2 containing a piston 3 which isoperatively connected with a motion plate 4. This plate 4 contains a camslot 5 coacting with a roller 6 which is operatively connected with themovable rails of the switch A. It will be seen, therefore, thatreciprocation of the piston 3 will cause movements of the switch A fromnormal to reverse positions and vice versa,

Operatively connected with the motion plate 1 are two movable contactmembers 15 and 16, which cooperate with fixed contacts 15 and 16respectively. These con tacts are so arranged that contact l5-15 isclosed in all positions of the switch except the reverse position, andthat contact 1()'-16 is closed in all positions of the switch except thenormal position.

The reference character V designates a valve device adapted to connectthe right hand end of cylinder 2 with a source of fluid pressure or withatmosphere, according as the movable member 7 of this valve device isdepressed or elevated. The member is biased to the elevated position bysuitable means which, as here shown, is a spring 8, the spring beingassisted by the pressure of the fluid on the under side of the member.lVhen in the elevated position the valve member 7 connects a pipe 9,-

leading from the right hand end of the cylinder, with atmosphere througha port 10. This valve member 7 is controlled by a solenoid and plunger11*", however, in such manner that when the solenoid is energized thevalve member is depressed in opposition to the force exerted by thespring 8 and the fluid pressure. lVhen in the depressed position, thevalve member disconnects pipe 9 from the port 10 and connects this pipewith a pipe 12 leading directly to the source of fluid pressure.

The left hand end of cylinder 2 is connected with the source of fluidpressure or with atmosphere by means of a valve device V controlled by asolenoid and plunger 11, which parts are similar to the correspondingparts V and 11 The lever L is arranged to rock between two extremepositions, known as normal and reverse positions, which positionscorrespond to the normal and reverse positions of the switch A.Operatively connected with the lever L is a contact member 13 whichengages with a fixed contact 14* from the normal position of the leverto an intermediate position known as the normal indicating position, andwith a fixed contact 14 from the reverse position to an intermediateposition known as the reverse indicating position. The solenoids 11 and11 of the motor device B are controlled by this lever-operated contactand by contacts 15 and 16 actuated by the motion plate 4, the manner inwhich this control is effected being explained hereinafter.

The movements of the lever L are controlled by indication meanscomprising, in the form here shown, two segments S and S rigidlyattached to the lever. The segment S is provided with a dog 17, whichcoacts with a latch 18 in such manner as to lock the lever in the normalindicating position when the lever is moving from reverse to normalpositions. The latch 18 is controlled by an electromagnet M adapted,when energized, to elevate the latch and so to permit the lever tocomplete its movement to the normal position. The segment is providedwith a dog 19, which coacts with a latch 20 to lock the lever in thereverse indicating position when moving from normal to reversepositions, and this latch 20 is similarly provided with an electromagnetM arranged when energized to elevate the latch and so-to release thelever.

The indication magnets M and M are controlled by a polarized indicationrelay C,

- which, in turn, is controlled by a polechanger P operated by themotion plate 4. These indication magnets are also controlled by acircuitcontroller D operatively connected with the lever L and arranged to bereversed during the movements of the lever from normal indicating tonormal positions, and from reverse indicating to reverse positions. Thecircuits for the control of relay C and of the indication magnets M andM will be explained hereinafter.

The operation of the apparatus shown in Fig. 1 is as follows:

As shown in this view. the switch A and the lever L are in normalpositions, and all other parts of the apparatus are in the correspondingpositions. Magnet ll and 11 M and M. are all deiinergized, butindication relay is energized in normal direction. hen it is desired tomove the switch A to the reverse position, lever L is swung in clockwisedirection by means of the handle 20 until it is stopped in the reverseindicatingposition by the engagement of dog 19 with latch 20. Contact1314 is then closed, so that the reverse magnet 11 is energized throughthe following circuit: from battery E, through wire 21, contact 1J314wire 22, contact 15-15 wire 23, winding of electromagnet. 11 and wires24, 25, 26 and 27 to battery E. Magnet 11 then operates to depress themovable memher 7- of the valve device Y thereby disconnecting theleft-hand end of cylinder 2 from atmosphere and connecting this end ofthe cylinder with the source of fluid pressure. Piston 3 is then shiftedto the right, thereby moving motion plate 4 to the right and so movingswitch A to the reverse position.

lVhen this position is reached, the circuit for magnet 11 is opened atcontact 15-15, so that member 7 of the valve device V returns to itselevated position, wherein the left hand end of cylinder 2 isdisconnected from the source of fluid pressure and is again connectedwith atmosphere.

This movement of the motion plate 4 reverses the position ofpole-changer P, so that the indication relay C becomes energized in thereverse direction, the circuit for this relay then. being from batteryE, through wire 28, contact 29, wire 30, contact 31, wire 32, left handfinger of pole-changer P, (which is then reversed), wire 34, winding ofrelay C, wire 33, right hand finger of pole-changer P, wire 85, contact86, wire 37, contact 38 and wires 26 and 27 to battery E. The consequentreversal of relay C causes contact 39 to swing to the rlght, whereuponthe reverse indication magnet M becomes energized through the followingcircuit: from battery E, through wires 28 and 40, neutral contact 41 ofrelay C, wire 42, right hand pointof polar contact 39 of relay C, wire43, left hand points of contact D, wire 44, winding of magnet M andwires 45, 46 and 27 to battery 'E. The consequent energization of magnetM causes latch 20 to be elevated out of the path of dog 19, so

that the movement of lever L to the reverseposition can then becompleted. During this final movement of the lever, circuit controllerDis moving to the opposite position, thereby deenergizing magnet M Inorder to move the Switch A from the reverse to the normal position,lever L is returned to its normal indicating position, in which positionit is stopped by the engage ment of dog 17 with latch 18. This closescontact 1314 so that the reverse operat ing magnet 11 is energizedthrough this contact and through contact 16l(5 operated by the motionplate 4. Magnet 11 then reverses the valve device V so that the righthand end of cylinder 2 is disconnected from atmosphere and is connectedwith the source of fluid pressure- Piston 3 is then driven to the left,thereby restoring switch A to its normal position, and when thisposition is reached magnet 11 becomes deenergized, due to the fact thatcontact memberz16 passes off from fixed contact '16. \Vhen the switchreaches the normal position, pole-changer P is restored to normalposition, so that the indication relay C be comes energized in thenormal direction. Contact 39 then swings to the left, so that indicationmagnet M becomes energized through this contact and through the righthand contact points of circuit controller D. Latch 18 is then elevatedout of the path of dog 17, so that the lever L may be moved to the fullnormal position. During this final movement of the lever, circuitcontroller D reverses, thereby deenergizing magnet M The parts of theapparatus are then in the positions in which they are shown in thedrawing.

It will be noted that the circuit for indication relay C includes fourcontacts 29, 38, 31 and 36. Contacts 29 and 38 are operatively connectedwith an auxiliary piston 47 which reciprocates in an auxiliary cylinder48 formed in the body of the valve device V the lower end of whichcylinder is connected by a port 50 with pipe 9 and so with the left handend of the main cylinder 2. The auxiliary piston 47 is biased downwardlyby a spring 49, and the contacts 29 and 38 are closed only when thispiston is in its lowest position. As soon as the movable member 7 ofvalve device V is de pressed to cause a reverse movement of the switch,fluid pressure is admitted to the auxiliary cylinder 48 and thispressure raises the auxiliary piston 47 and so opens contacts 29 and 38.Then when the movement of the switch is completed and valve member 7returns to its initial position, the air in the left-hand end ofcylinder 2 flows out through the exhaust port in valve device V and whenthe pressure is reduced to a very low value, piston 47 returns to itsinitial position wherein contacts 29 and 38 are closed.

The valve device V is provided with an auxiliary piston and cylinderwhich are similar to the corresponding parts associated with valvedevice V It will be seen from the foregoing that I have provided apressure responsive device for each end of the main cylinder 2, which isso arranged that any pressure in the air line bet-ween the cylinder andthe corresponding main valve device will interrupt the indicationcircuit and so will prevent completing the movement of the lever L. Bythis means, when an indication is received the operator is assured thatthe main cylinder 2 is relieved of all pressure that would tend to causea false movement of the switch A.

The apparatus shown in Fig. 1 provides no protection other than thatprovided by the indication circuit itself. Further protection may besecured by means of the apparatus shown in Fig. 2, and which apparatusconstitutes the preferred form of my invention. Referring to Fig. 2, thebody of the valve device V is provided with a valve chamber 51, thelower end of which is connected with the intake and exhaust ports of thevalve device by a. port 55. The pipe 9 leading from the left-hand end ofthe main cylinder 2, is connected with the valve chamber 51 at anintermediate point in this chamber. The upper end of chamber 51 isopened to atmosphere through an exhaust port 54. The chamber 51constitutes an auxiliary cylinder which is provided with a piston 52biased to a depressed position by a spring 53, and when the piston is inthis position the pipe 9 is disconnected from port 55 and is connectedwith atmosphere through the exhaust port 54. When the movable member 7of valve device V is depressed, fluid pressure enters the lower end ofchamber 51 and immediately raises piston 52 to such position thatpressure is supplied to the pipe 9 and so to the lefthand end of themain cylinder 2. This upward movement of piston 52 opens the indicationcontacts 29 and 38. lVhen the movement of the railway switch has beencompleted and valve member 7 is restored to its initial position, theleft hand end of main cylinder 2 is opened to atmosphere through exhaustport 10, and when the pressure is reduced to a certain value piston 52returns to its initial position, so that the left-hand end of cylinder 2is then open to atmosphere through port 54, and is disconnected from theintake and exhaust ports of the valve device V Contacts 29 and 38 do notclose until piston 52 reaches such position that cylinder 2 is opened toatmosphere through port 54.

The normal valve device V is provided with auxiliary apparatus which issimilar to the apparatus associated with the reverse valve device V Itwill be observed that in the form of my invention shown in Fig. 2 aby-pass valve is located between each main valve and the cylinder 2, andthat this by-pass valve is operated when air passes from the main valvetoward the cylinder, but is not responsive to pressure of the exhaustfrom the main cylinder toward the main valve. This by-pass valverelieves the main valve from the duty of carrying the exhaust air, andgives the operator a definite indication that both ends of the maincylinder 2 are opened to atmosphere at the completion of each movementof the lever L.

Although I have herein shown and described only two forms of apparatusembodying my invention, it is understood that "arious changes andmodifications may be made therein within the scope of the appendedclaims without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is:

1. In combination, a railway switch having normal and reverse positions,a cylinder, a piston movable therein and operatively connected with theswitch, a source of fluid pressure, a normal and a reverse valve for thetwo ends of said cylinder respectively each biased to one positionwherein it connects the corresponding end of the cylinder withatmosphere and movable to a second position wherein it connects thecoresponding end of the cylinder with said source of fluid pressure, anormal and a reverse magnet for said normal and reverse valves and eacharranged when energized to move the corresponding valve to said secondposition, a lever having normal and reverse positionsas well as normalindicating and reverse indicating positions, means controlled by saidlever and said switch for energizing said normal magnet when the leveris in normal indicating position and the switch is not in normalposition and for deenergizing said normal magnet when the switch reachesthe normal position, means controlled by said lever and said switch forenergizing said reverse magnet when the lever is in reverse indicatingposition and the switch is not in reverse position and for deenergizingsaid reverse magnet when the switch reaches the reverse position, anormal indication device for locking said lever in normal indicatingposition when moving toward normal position, a reverse indication devicefor locking said lever in reverse indicating position when moving towardreverse position, means operatively connected with said switch forreleasing said normal or said reverse indication device according as theswitch is in normal or reverse position, and means for preventingrelease of either of said indication devices unless the pressure in eachend of said cylinder is below a given valve.

2. In combination, a railway switch having normal and reverse positions,a cylin der, a piston movable thereinand operatively connected with theswitch, a source of fluid pressure, a normal and a reverse valve for thetwo ends of said cylinder respectively each biased to one positionwherein it connects the corresponding end of the cylinder withatmosphere and movable to a second position wherein it connects thecorresponding end of the cylinder with said source of fluid pressure, anormal and a reverse magnet for said normal and reverse valves and eacharranged when energized to move the corresponding valve to said secondposition, a lever having normal and reverse positions as well asnormalindicating and reverse indicating positions, means controlled by saidlever and said switch for energizing said normal magnet when the leveris in normal indicating position and the switch is not in normalposition and fordeenergizingsaid normal magnetwhen the switch reachesthe normal position, means controlled bysaid lever and said switch forenergizing said reverse magnet when the lever is in reverse indicatingposition and the'switch is not in reverse position and for deenergizingsaid reverse magnet when the switch reaches the reverse position,indication means for looking said lever in normal indicating and reverseindicating positions, and means for controlling said indication means bythe 130 sitions of said switch and by the pressure in each end of saidcylinder.

3. In combination, a railway switch having normal and reverse positions,a cylinder, a piston movable therein and operatively connected with theswitch, a source of fluid pressure, a normal and a reverse valve for thetwo ends of said cylinder respectively each biased to one positionwherein it connects the corresponding end of the cylinder withatmosphere and movable to a second position wherein it connects thecorresponding end of the cylinder with said source of fluid pressure, anormal and a reverse magnet for said normal and reverse valves and eacharranged when energized to move the corresponding valve to said secondposition, a lever for controlling said magnets, indication apparatuscontrolled by the positions ofsaid piston for locking and releasing saidlever, and means for preventing said apparatus from releasing said leverunless the pressure in each end of said cylinder is below a given value.

4. In combination, a railway switch, a cylinder, a piston movabletherein and operatively connected with said switch, means for admittingfluid pressure to one end or the other of said cylinder to move saidswitch and for releasing said pressure after the switch has been moved,a lever for controlling said means, and indication means for said levercontrolled by the positions of said piston and effective to indicate amovement of the switch only after the release of fluid pressure hasoccurred. 7

5. In combination, a railway switch, a cylinder, a piston movabletherein and operatively connected with said switch, means for admittingfluid pressure to one end or the other of said cylinder, a lever forcon- 7 trolling said means, indication apparatus controlled by thepositions of said piston for locking and releasing said lever, and meansfor preventing said indication apparatus from releasing said leverunless the pressure in each end of said cylinder is below a given value.

6. In combination, a railway switch, a cylinder, a piston movable in thecylinder and operatively connected with the switch, two valves foradmitting fluid pressure to the two ends of said cylinder respectively,a lever for controlling said valves, indication apparatus governed bythe positions of said piston for locking and releasing said lever, andpressure responsive'means located between each valve and thecorresponding end of the cylinder for controlling said indicationapparatus.

7. In combination, a railway switch, a cylinder, a piston movable in thecylinder and operatively connected with the switch, two valves foradmitting fluid pressure to the two ends of said cylinder respectively,a

lever for controlling said valves, indication apparatus governed by thepositions of said piston for locking and releasing said lever, and meanslocated in the connection between each valve and the corresponding endof the cylinder and responsive to the fluid pressure in such connectionsfor also controlling said indication apparatus.

8. In combination, a railway switch, a cylinder, a piston movable in thecylinder and operatively connected with the switch, two valves foradmitting fluid pressure to the two ends of said cylinder respectively,pressure responsive means located between each valve and thecorresponding end of the cylinder, and indication apparatus controlledby said means.

9. In combination, a railway switch, a cylinder, a piston movabletherein and operatively connected with said switch, means for admittingfluid pressure to one end or the other of said cylinder to move saidswitch and for releasing such pressure after the switch has been moved,and indication means controlled by the pressure in each end of saidcylinder and eflective to indicate amovement of the switch only afterthe release of pressure has occurred.

10. In combination, a railway switch, a cylinder, a piston movabletherein and operatively connected with said switch, means for admittingfluid pressure to one end or the other of said cylinder to move saidswitch and for releasing such pressure after the switch has been moved,and indication means controlled by the positions or said piston andefiective to indicate a movement of the switch only after the release ofpressure has occurred.

11. In combination, a railway switch, a cylinder, a piston movabletherein and operatively connected with said switch, means for admittingfluid pressure to one end or the other of said cylinder, movable membersresponsive to the pressure in each end of said cylinder, a contactactuated by each member and closed only when the pressure in thecorresponding end of the cylinder is below a given value, and indicationapparatus controlled by said contacts.

12. In combination, a railway switch, a cylinder, a piston movabletherein and operatively connected with said switch, means for admittingfluid pressure to one end or the other or" said cylinder, a lever forcontrolling said means, movable members responsive to the pressure ineach end of said cylinder, a contact actuated by each member and closedonly when the pressure in the corresponding end of the cylinder is belowa given value, and indication apparatus for said lever controlled bysaid contacts.

13. In combination, a railway switch, a cylinder, a main piston movablein the cylinder for actuating the switch, a valve chamber for each endof said cylinder, a two-way valve for each chamber biased to oneposition wherein it connects the chamber with atmosphere and movable toa second position wherein it connects the chamber with a source of fluidpressure, an auxiliary piston in each chamber biased to one positionwherein it connects the corresponding end of the cylinder withatmosphere and movable to a second position by a given pressure in thechamber wherein it connects the corresponding end oi": the cylinder withthe chamber, a lever for governing said valves, and indication apparatusfor said lever con trolled by the positions of said main piston and ofsaid auxiliary pistons.

14. In combination, a railway switch, a cylinder, a main piston movablein the cyl inder for actuating the switch, a valve chamber for each endof said cylinder, a two-way valve for each chamber biased to oneposition wherein it connects the chamber with atmosphere and movable toa second position wherein it connects the chamber with a source of fluidpressure, an auxiliary piston in each chamber biased to one positionwherein it connects the corresponding end of the cylinder withatmosphere and movable to a second position by a given pressure in thechamber wherein it connects the corresponding end of the cylinder withthe chamber, a lever for governing said valves, indication apparatuscontrolled by the positions of said main piston for locking andreleasing said lever, and means controlled by said auxiliary pistons forpreventing release of said lever unless both auxiliary pistons are inthe positions to which they are biased.

15. In combination, a railway switch, a cylinder, a main piston movablein the cylinder for actuating the switch, a valve chamber for each endof said cylinder, a two-way valve for each chamber biased to oneposition wherein it connects the chamber with atmosphere and movable toa second position wherein it connects the chamber with a source of fluidpressure, an auxiliary piston in each chamber biased to one positionwherein it connects the corresponding end or" the cylinder withatmosphere and movable to a second position by a given pressure in thechamber wherein it connects the corresponding end of the cylinder withthe chamber, and indication apparatus controlled by the positions ofsaid auxiliary pistons.

In testimony whereof I afiix my slgnature in presence of two witnesses.

CHARLES 1V. DUNHAM.

Witnesses:

A. HERMAN WEGNER, D. S. GUsERvrrz.

